A shading method developed by James Blinn in 1977 that uses diffuse, specular, eccentricity, and refractive index attributes. Increased control over the specular component makes for good representation of metallic surfaces. The Blinn shading model was initially inspired by Phong's work at the University of Utah, and Blinn's desire to represent a more accurate specular lighting model. Blinn then spent many weeks researching extensively at the University library, discovering many papers dating back to the 1920s by an "optical illumination society" and more recent work was done by Torrance and Sparrow at the University of Minnesota. What Blinn did was to codify the theory into a practical light reflection model that was both physically based and accurate.